Himalayan glaciers to disappear by… when?

Reader enragedparrot asks the rather sensible question, which appears to have been somewhat neglected in the vast war of words of 2035, 2350, and quite what is the source for what: if 2035 is badly wrong, what is the right date?

The answer, of course, is that I don’t know. But I may be able to tell you something useful along the way. If you’ve seen a better answer, please point me at it.

Lets go back to physical reality for a bit. The lapse rate is about 6.5 K per kilometer – which means, all else being equal and taking the rough with the smooth, that if you go vertically up 1 km it will get 6.5 K colder. So, again using a very broad brush, if a given patch of snow is going to just-not-melt all through the year at a given altitude, then about 200 years from now it will just-not-melt about 1 km higher up (this ignores enormous possible changes – precipitation is obviously very important, and shifts in the monsoon could have a massive effect on the glaciers – but that is yet more complexity). Since there is quite a lot of “higher up” available in the Himalayas, that pretty well guarantees there will be *some* glaciers there in 200 years time, barring absurd levels of GW. Attempting to predict more than 200 years ahead is a waste of time, so I won’t try (and I don’t say much in favour of 200, either).

To work out exactly how much, you’d need to run a super-spiffy hi-rez GCM, and we don’t have those. More plausibly, you could take a larger-scale warming prediction and feed it into a GIS, which would know the height and accumulation rate of all the existing glaciers, and then make a guess at their future response. As I recall, there are some Gregory / Oerlemans papers doing an even broader-brush version of this, but I’ve forgotten the details.

[Yes, fair point. I won’t pretend to have done an exhaustive cost-benefit analysis of the issue. But I did want to note that what appears to be commonly said “oh no! all the snow will melt! there will be no water to drink!” is nonsense -W]

I can just imagine the Indians agreeing to China building a dam or two in the headwater regions of the Indus and Brahmaputra. Perhaps they would if they got 50:50 control/access. Interesting political times, between what will then likely be the world’s two superpowers.

And I wonder what the Bangladeshis would think of India damming the Ganges, that holiest of all the rivers for Hindus. Mind you, I suppose the Bangladeshis could build some desalination plants along their new waterfronts.

“… multi-annual data (up to not, vert, similar40 yrs) of water flow and sediment concentrations were used for inferring the variations in water flow and sediment loads on longer time scales. In most previous studies of Himalayan Rivers, there has been a general lack of long term water flow and sediment load data. In the present study, we carried out high frequency sampling, considered long term discharge data and based on these information, discussed the temporal and spatial variations in water discharge and sediment loads in the rivers in the Himalayan region. The results show that, >75% of annual sediment loads are transported during the monsoon season (June through September).”

Sounds like there might be a bit of a problem with silt backing up behind the dams, and loss of the river deltas.

From Wikipedia: “In Nepal, the temperature has risen 0.6 degree C over the last decade, whereas the global warming has been around 0.7 degree C over the last hundred years.”
-could the Himalayan region experience more warming than the rest of the world? If this 0.6 degrees/decade continues to the future, it is 6 degrees by 2110.

From Wikipedia
* The Siachen Glacier
from an altitude of 5,753 m (18,875 ft) above sea level at its head at Indira Col (pass) on the China border down to 3,620 m (11,875 ft) at its terminus
*Gangotri Glacier
4120 to 7000 m above sea level (7000m is a bit unrealistic height for a glacier – it’s located in so steep slope it would fall down if the glacier below would vanish…)
*Yamunotri Glacier
4,421 metres to a height 6,387 mtrs
From Wikipedia:
“The mountain lakes are known to geographers as tarns if they are caused by glacial activity. Tarns are found mostly in the upper reaches of the Himalaya, above 5,500 metres.”
*This gives the indication that melting occurs at least in 5500 metres – add the 1km suggested you get 6500m And you have almost no valleys in this height that could host a glacier. Given that the region has warmed way faster than the most of the rest of the globe, one might half the time (200 years) and add (wild guess) some hundred meters to the height of negative glacier growth (hah).

Given that
(http://www.terradaily.com/reports/Wet_Desert_Of_India_Drying_Out_999.html) “The local weather department recorded the decrease in rainfall in the last two monsoons at closer to 30 percent, with the area getting 8.7 metres during the 2006 monsoon, according to deputy director general D. Chakraborty.” and “”The entire pattern of rain and the intensity of rain is changing,” he added, pointing to the unusual amount of rainfall and floods last year in the usually parched western desert state of Rajasthan, on the same latitude.” it might be said that eastern glaciers of The Himalayas may be receding faster than the western ones and that the time frame for the disappearance of these is less than 200 years.

The only saving issue for the glaciers I can see is the possibility of increased fall precipitation from the Siberian side of the Himalayas, but these rains will likely hit the Tien Shan and Kunlun Shan mountains and not be enough for the Himalayas.

Sorry I forgot to mention the airborne soot which effects the rate of melting once it lands to the glacier. The glaciers will recieve soot during the monsoon period. The cloud droplets (visible as mist up in the glacier) will be packed with it. This is clearly seen at the glacier terminuses where it accumulates by the melt.

RE jyyh #6: “In Nepal, the temperature has risen 0.6 degree C over the last decade, whereas the global warming has been around 0.7 degree C over the last hundred years.”

So jyyh, extrapolating, why hasn’t Nepal warmed by 6C over the last hundred years? Aren’t you confusing short-term fluctuations with fundamental shifts in climate? If not, what do you say to the people who claim global warming has stopped because the temperature has not risen for the last decade?

[Yes, indeed he is. This kind of extrapolation is where the melt-by-2350 claim comes from, and it is part of why it is so badly wrong. We should not, obviously, be placing any reliance on 10-year temperature trends -W]

“The lapse rate is about 6.5 K per kilometer – which means, all else being equal and taking the rough with the smooth, that if you go vertically up 1 km it will get 6.5 K colder.”

I hate to play devil’s advocate, but would you expect all else to be even close to equal? Even assuming a 6.5K increase in global average temperature (which corresponds to a highly unlikely 16-fold increase in CO2 for a sensitivity of 1.6K assuming all increase is GHG-caused), you’d think the cold areas of the planet (like the Himalayas) would warm disproportionately more than the warm areas, given that the tropics already trap almost 100% of the outgoing radiation with water vapor.

[Climate sensitivity is 3 oC not 1.6. The tropics warm *less* under GW not more – see any of the std GCM maps. The water vapour argument is irrelevant. Rather *more* relevant is that the lapse rate depends on the humidity.

Overall: no, I would not expect all else to be equal. This isn’t a prediction, it is just an illustrative statement -W]

Just a comment to “there is quite a lot of ‘higher up’ available in the Himalayas”.

If you want to use simple lapse rate arguments, then you need to look at the typical altitudinal range of the glaciers rather than that of the Himalayas. Glaciers in balance, are in balance with their own local micro climate. For example lets make the assumption that half the altitudinal range is accumalation area, and the other half is ablation area. Lets also assume that the Equilibrium Line Altitude is shifted vertically 1km per 6.5degC. So, for a himalayan glaciers covering an altitudinal range of 2km (see comment 6 on this thread), 6.5degC would be enough to make the entire glacier into an ablation area.

However, this is all very crude. If any of you are interrested in glacier response times and simple models then I recommend J.Oerlemans free book “Minimal glacier models”. It is available at his website.

No its not. Read my previous link to Schwartz 2008. He gets 1.9 +- 1 with a study far more convincing than GCMs with all their fudge factors. Given the enormous political pressure to come in with high sensitivity estimates, and watching the way they are creeping down, I am betting the real number is between 1.5 and 2.

“The water vapour argument is irrelevant. Rather *more* relevant is that the lapse rate depends on the humidity.”

Last I checked, humidity is H2O.

[Stop to think before you post. You wrote “given that the tropics already trap almost 100% of the outgoing radiation with water vapor”. This is largely irrelevant. As I said, what is more important is the effect of WV on lapse rate -W]

From the first para of JA’s posting: “In fact, current GCMs which account for these factors [aerosols] do an excellent job of reproducing the observed warming”

With aerosol values that vary from model to model. And you call Schwartz trash. Why is it so hard for you guys to understand that if the models require different values of an objectively fixed parameter like aerosols in order to fit the data, then fitting the data does not prove the models’ veracity?

The main range of the Himalaya have an interesting difference in terms of water resources from all other alpine regions. The main melt season is during the summer monsoon, which is also the main precipitation and main accumulation season. Thus, when Himalayan glacier melt summer runoff declines are not as severe as in other where streamflow is minimum in summer as is precipitation. Gangotri Glacier
In terms of the black carbon soot issue, note that this deposition is not importance on debris covered sections, they already have a high albedo, nor are they important in the areas with frequent new snow at all times of the year, most of the accumulation zone on large glaciers. Since they are getting new snow during the melt season, the black carbon and soot is important only near the equilibrium on glaciers in the main portion of the Himalaya.Khumbu Glacier

Maybe I didn’t use the right language, but FWIW, here’s my undergrad physics intuition. The tropics are saturated, so heating them is heating wet air which does not exhibit the same temperature gradient as dry air (you’re hitting the latent heat ceiling). So as a rule of thumb, wherever it is dryer and colder, you expect more warming, and wherever it is wetter and and hotter you expect less. It is dryer and colder at high altitudes, and away from the equator, hence Himalayan warming (Himalayas are at 30 degrees lat).

[I don’t think so. Your intuition will convince you only, of course. Did you read the dynamical link? The other aspect is the hot-land-cooler-sea bit, which is evap related -W]

That doesn’t explain why the north pole warms more than the south pole, but they are very different: south pole is a huge ice continent surrounded by ocean. North pole is a smaller ice ocean surrounded by continent, in which a lot of the ice melts so it may just be albedo differences.

Interesting idea (to me) : simulate a model earth that is rotationally symmetric about the pole-pole axis. So you have a circular arctic ocean, then a ribbon (annulus) continent circling the globe south of that until, say the latitude of Tasmania in Australia, then an annulus southern ocean, and finally a circular antarctic. Assuming similarly rotationally symmetric initial conditions the solution to the fluid equations will be rotationally symmetric, so you can ignore longitude and make a much finer grid in your simulations.

The grid would now just be over an annulus, with the inner circle corresponding to the surface of the earth, and the outer circle corresponding to the top of the atmosphere (actually, you’d need to add portions of an inner-inner circle to simulate the oceans, but it would still be 2-D not 3-D). I wonder if that would be enough to capture gross climate features like tropics-pole temperature gradient and CO2 sensitivity.

Not sure if the article readable without a subscription. I see they’ve adopted the execrable pinheaded Examiner blog comment approach, a filter that won’t allow links in postings, but chopping off the http://www seems to get them past their filter.

The Kargel presentation seems thorough, but is a bit thin on anything to do with the big Chinese rivers. It also fails to mention Hansen’s new paper with what looks to be most of the leading Chinese glaciologists. Its opening paragraphs (pasted below) set the regional scene with some rather strong statements, most of which appear to be based on recent work by the authors.

Mauri, would it be possible to get some interpretation here?

—————————

“Glaciers on the Tibetan Plateau, sometimes called Earthâs ‘third pole,’ hold the largest ice mass outside the Polar Regions. These glaciers act as a water storage tower for South and East Asia, releasing melt water to the Indus, Ganges, Brahmaputra, and other river systems, providing fresh water to more than 1 billion people. Glacial melt provides up to two-thirds of the summer flow in the Ganges and half or more of the flow in other major rivers. One-quarter of the population of China is in western regions where glacial melt provides the main dry season water source.

“Tibetan glaciers have been melting at an accelerating, alarming rate over the past decade, raising the threat that many of the glaciers could be gone by midcentury. As glaciers recede and release stored water, flow temporarily increases, but the future fresh water supply is threatened. Once headwater glaciers are gone, however, a dramatic decline in dry season water availability may ensue. Total precipitation may increase with global warming, but a likely result of glacier loss will be heavier spring floods and much reduced fresh water availability during subsequent dry seasons.

“Climate on the Tibetan Plateau is changing rapidly; over the past three decades, the large area at altitude above 4,000 m has warmed 0.3 Â°C per decade, which is twice the rate of observed global warming. Climate change on the plateau may have large regional effects, for example, on the Asian monsoon, and even global repercussions. Glacier retreat in the Tibetan Plateau presumably is driven by warming due to increasing greenhouse gases, but the rapidity of glacier retreat and the up to 0.3 Â°C warming of per decade during the past 30 years suggest additional mechanisms may be involved.”

“… Look, whaddaya talk
Whaddaya talk, whaddaya talk
Whaddaya talk, whaddaya talk
Where do you get it?
Whaddaya talk?
You can talk, you can talk
You can bicker, you can talk
You can bicker, bicker, bicker
You can talk, you can talk
You can talk, talk, talk, talk,
Bicker, bicker, bicker
You can talk all you want
But it’s different then it was
No it ain’t, no it ain’t
But you gotta know the territory ….”
— Meredith Willson (c)1957http://www.endresnet.com/mmsounds.html

Steve Bloom, what is the source of your quotation (#25)? I did not find it in the page of Hansen’s press release you linked.

While it is true that a billion people live in the river basins which have glaciers in the headwaters in the Tibetan Plateau or the Himalayas, it is certainly exaggeration that a billion people crucially depend on meltwater from glaciers. See Page 38 of Kargel’s presentation. While it just mentions Himalayan glaciers, the glaciers in the Tibetan Plateau are ever thinner.

But it may be true (though I have not confirmed) that a billion people depend on meltwater from snow and ice together (mainly from snowpack). Maybe the confusion is caused by someone who used “glacial meltwater” to mean this, by analogy with “glaciology” which means the study of snow and ice not limited to glaciers.

While the source of CO2 emissions and carbon soot are the same, the cost and the technologies used to reduce them are not. Policy focused on soot could well be more achievable and of more benefit to glaciers and polar ice than those focused on CO2.

Long term, most of the worrisome projections are based on positive feedbacks. Glacier and polar ice loss are major feedbacks. Less positive feedback mean less damage from CO2. Long term, reducing CO2 without eliminating potential positive feedbacks could negate the benefits of CO2 reductions.

I understand the answer of my question (#27). As Hank Roberts (#28) showed, effectively the same message as quoted by Steve Bloom (#25) is included in the first paragraph of a paper in Proc. Nat’l Acad. Sci. by Xu, Cao, Hansen, Yao et al. which is also available from GISS as http://pubs.giss.nasa.gov/docs/2009/2009_Xu_etal.pdf .

The relevance of glacier melt water as water resource is the subject of the introductory paragraph of the paper. It is not the main original achievement of the paper. From the situation where Yao who is likely to have good knowledge about this subject is among the authors, I wished to believe that this part is also authoritive. But I suspect that the it was added by some other author at the last minute without detailed consulting with Yao and that the reviewers of PNAS did not care this part.

The first paragraph is very similar to a paragraph in the Secction 3.4.3 (page 187) of IPCC AR4 WG2, except a new reference (Qiu 2008, Nature) is added. Both heavily rely on the paper by Barnett, Adam and Lettenmaier (2005 Nature). I have not yet checked the original articles of Singh and Bentsson (2004, Hydrol. Process) and Gao and Shi (1992, J. Desert Res.). But the title suggests that the Singh and Bentsson paper is a case study of a certain basin.

The sentence of the Barnett et al. paper which quotes Gao and Shi is as follows:

“In China, 23% of the population lives in the western regions, where glacial melt provides the principal dry season water resource.”

It means that 0.25 billion people live in western China, and “glacial melt” water is important there. But it does not necessarily mean that glacier melt water is important for all the population living there. The problem may be either the meaning of “glacial”, or the fraction of the sub-regions of western China where glaciers are really important.

I am afraid the Barnett et al. paper is not well organized, probably because it was prepared in a rush to be in time for IPCC AR4. In my opinion, it is a good reference about the impotance of snowpack as water resources for which the paper devoted most of words, but it is not a good reference about glacier meltwater which is mentioned just in passing near the end of the paper.

[Thank you for this comment, This is the kind of valuable subtle analysis that we see all too often. Alas, I can see myself in a discussion on this topic on wikipedia, attempting to make people appreciate these distinctions. Would they listen? Not a hope -W]

Excuse me. The subject of my previous comment (#33) was just the first paragraph of the quotation by Steve Bloom (#25) which mentioned the importance of glacier melt water as water resource. I did not mean to discuss the actual rate of melting or the mechanism there.

Let me see if I can explain why I think that focusing on things other than CO2 is a better strategy for those trying to prevent climate change.

[I’ll tell you why people object, validly, to this, and it has nothing to do with the science:

In an idea world a dispassionate discussion of all the various factors is an excellent idea. In this world, the scientist should indeed be doing just that. And the bloggers who blog about science should do the same. But in the sphere of politics and the meeja, any thing that is trivially spinnable as “CO2 not the culprit” needs to be handled with care -W]

Here’s what I think we can agree on. CO2 has a radiative effect. Climate has a temperature sensitivity to various levels of CO2. W says JA has it about right. Increases or decreases in temperature above or below climate sensitivity arise from feedbacks.

According to Hansen positive feedbacks can raise temperatures 2 or 3 times the CO2 effect or more. Eliminating positive feedbacks would reduce the global warming potential of CO2. I would defer to W about feedbacks or any other area of climatology.

Reducing CO2 is good and the only way to do it is to stop burning hydrocarbons for energy.

You want to measure progress by how much CO2 emissions and concentrations are reduced. I want to measure progress by how much carbon burning has been replaced.

Is it likely that governments will globally or individually control CO2 in the near term? No. The UN climate structure is collapsing. Australia has already voted it down. Prospects in the US are dim. Russia, China and India aren’t interested. You may be willing to wait for a magical political conversion. I am not.

Back to soot and ice which has gotten more attention since a NASA study reported that soot and decadal ocean oscillations were greater drivers than temperature of the 2007 Arctic ice loss. Soot is a traditional non controversial pollutant. No one argues that soot is necessary to life on the planet. Regulating soot is politically possible.

With respect to the Xu et al, (2009) paper in PNAS looking at the Zuoqiupu Glacier. The staked glacier referred to in Figure 4 glacier is a small Himalayan Glacier extending from 5000 m to 5500 m. The glacier has limited debris cover and limited elevation range. On Himalayan and Tibetan Glaciers the larger glaciers have substantial areas that are typically referred to as the dry snow zone, where accumulation dominates and black carbon-soot (BC) deposition has no impact. Then the lower section of the glaciers with considerable debris on them also have limited sensitivity to BC. The areas with a couple hundred meters of the equilibrium line is the zone where BC can have an impact. On the staked glacier adjacent to the Zuoqiupu this is the entire glacier. On the neighboring Laigu Glacier 32 km long ranging from 4000 m to 5800 m, the story is much different. On this glacier the terminus region is debris covered, and an extensive dry snow zone exists. There is no doubt that BC will affect melt rates in the intermediate elevation zone. The limiting factors is how much of each glacier is in this zone and what is the percentage increase in the melt rate for BC concentration increases. The former can be answered today. The latter cannot. The fact that BC has increased indicates the potential problem. These glaciers are often avalanche fed, avalanches are the source of most of the debris cover, thus there is considerable dust and debris as well to enhance ablation-BC is not the only material. As you north to colder, low ppt and less debris covered glacier, BC would likely have a greater potential. The scale of the problem, is unknown, since we do not have melt rate data for different surface concentrations. The paper raises the quantitative potential but cannot be relied on to provide even an estimate of the BC impact on melting for Himalayan glaciers. Take a look at the Gangotri Glacier I added an image from GE of the Staked glacier and the nearby Laigu Glacier.

But in the sphere of politics and the meeja, any thing that is trivially spinnable as “CO2 not the culprit” needs to be handled with care -W

I’m not saying “CO2 is not the culprit” or disputing the science.

[I know you’re not, and I didn’t say you were -W]

If any deniers are reading this, please do not use anything I write to further your arguments.

[This, however, is a problem – or at least it is, if you think they’ll be polite enough to obey your wishes in this way. Of course, we’re not really talking about the debate here on this blog, but the debate you’d like to see in the wider sphere, and the same applies there: saying something that can be easily badly spun, and adding “please don’t spin this”, won’t work. If *you* do it, I’ll just call you naive. If someone with meeja-savvy does it, then I’ll know they are just grabbing headlines and damn the problems they’ll cause -W]

Saying that factors other than temperature cause feedbacks and failure to address those causes undermines the benefits of reducing CO2 is not intended to diminish the danger of CO2.

Of course what people think about the science is often heavily influenced by their political leanings because the policies proposed are so contentious.

A lot of effort has gone into getting governments to set a price on carbon high enough to force alternatives. The unfortunate political reality is it’s not happening. Hank says delay is the deadliest form of denial. I say it is a delayer who continues to knock on a locked door.

My whimsical request to deniers aside, I hope you’re not saying one should not state the truth for fear the truth will be misconstrued. That’s assuming I’m correctly describing the effect of soot on ice. If not, corrections are welcome.

What is at risk of harm? Acknowledging and studying the effect of soot on ice can’t harm the science. It is the science. Does it undermine some specific desired policy? Perhaps, but that’s a good thing if it steers us to better policy.

[If *you* say any of these things, there is no problem of course. But it is quite common to see press releases for papers that “spin” the paper by making deliberately controversial statements rather tenuously justified by the paper. And then when it all blows up, they say “ah but if you read the paper not the press release as of course we intended you to, you’d understand”. However, highly placed people whose word will be picked up by the meeja have a further responsibility than this, not merely not to spin their own stuff but to be careful how their words will be spun by others. So, clearly, one should state the truth. But if someone were to say something like “soot is far more important than CO2 [insert sub clauses here] in terms of Himalayan glacier decline [insert yet another pile of subclauses here] oh of course we only mean for a few small glaciers etc etc” then that is so trivial to mis-spin that they should know better.

“Acknowledging and studying the effect of soot on ice can’t harm the science. It is the science” – of course. I’ve already said that. Why are you repeating it? Within the context of science, there is no problem. When you push it into the meeja though you have to be more careful -W]

The debate I’d like to see in the wider sphere is not whether the world should undergo an energy transformation, but how to go about it. And yes, I am biased toward bottom up rather than top down solutions.

highly placed people whose word will be picked up by the meeja have a further responsibility than this, not merely not to spin their own stuff but to be careful how their words will be spun by others.

It ain’t easy. It didn’t take me very long in my comedy career to learn that most meeja types approach subjects with their own preconceived notions. It took a bit longer to learn how to turn interviews my way. Luckily for us all, the meeja has so far shown no interest in my thoughts on climate policy.

I’m in the middle of trying to track down the ultimate source of a claim made by Kehrwald et al about meltwater contributions to the Indus, Ganges and Brahmaputra rivers and have had to wade through a lot of other tosh along the way. Barnett et al has been the inspiration for much of it. It’s a terrible paper (although not as bad as Kehrwald et al). It took a crude tally of large manmade reservoirs, decided that this was the total storage capacity for the world’s river basins, combined this capacity with a model showing which regions were mostly reliant on snowmelt, and decided that one sixth of the world’s population will face severe consequences if glaciers keep shrinking.

(‘Valuable subtle analysis’? Maybe not. But I’m fed up. It takes hours and hours chasing these Chinese whispers. Why can’t AGW-related studies do what they say on the tin? Is it so hard to use the stated ingredients and use them in a proper manner? NGOs are mostly to blame but Kehrwald et al shows that peer-reviewed crap can be equally crap. It looks likely that the Kehrwald claim was a misattributed misrepresentation of misattributed claims plucked out of thin air by the authors of a 2004 UNEP report. Bastards!)

I do not mean that glaciers are not important as water resources. I just mean that a billion people do not depend on them. Probably tens of millions of people depend on them. It is more important than the fraction in average runoff suggests, because glaciers are reservoirs which can smooth year-to-year fluctuation of water supply.

In my opinion, the snow cover part of Barnett et al. paper is not a crap, thought it is not well finished. The quality of analysis is certainly terrible in the standard of regional case studies, but to have a global aggregation we often need bold generalizations.

“Australia has already voted it down. Prospects in the US are dim. Russia, China and India aren’t interested.”

Those 5 countries constitute 80% of the worlds coal reserves.

China currently consumes 42% of the worldwide production of coal, their own domestic supplies run out in 40 years. They are unlikely to want to be dependent on the other members of ‘Big Coal’. Hence they are engaged in a crash ‘alternative energy’ program.

The same is true of the EU, they are already dependent on the Russian Federation for a significant portion of their Oil and Natural gas, they don’t want to be dependent on the Russian Federation for coal as well.

The degree to which national leaders ‘believe’ in Global Warming is proportional to whether or not they are goring someone else’s horse or their own.

Senator Baucus of Montana and Senator Byrd of West Virginia are quite happy to believe that Global Warming caused by imported oil will cause some great catastrophe, there is no amount of science that will convince them that global warming caused by burning coal will cause some great catastrophe. Senators don’t vote to send their own constituents to the unemployment line.
I count 32 ‘Coal is good’ votes in the Senate. Central Appalachian Coal reserves are declining quite rapidly. In another 20 years those 32 votes probable dwindle to 16 votes.

Hence, a focus on mitigating the non-CO2 impacts of burning coal in ‘Big Coal’ nations is probably the only politically feasible course of action.

Hansen’s focus on soot and aerosol’s rather then CO2 is politically astute from a Geopolitical perspective.

Climate science has become part of a narrative that is fed by scandal, however overblown it may be. Scientists are being thrown under the bus and UN officials are not far behind. The press feeds on contention and fall from grace. Those caught in the narrative should have everybody’s sympathy.

So who is most grotesque spinner – the assumed biased reporter, the unwitting scientist who speaks easily spun words or partisans looking for ammunition?

I’m not a young historian but, for the sake of discussion, will take a stab at HR’s documentation.

Claim 1: “The impact of global warming has been exaggerated by some scientists”
Does James Hansen exaggerate? Yes.

[This isn’t a good question. “By some” is always silly – because there is *always* someone who will say something silly. But since we don’t *know* the future impacts, how can you confidently assert they are overdone? -W]

I have got a (perhaps new) concept in communication of the issues of environmental change, that is, “an honest alarmist”. I hope this will have some effect to reduce the tension mentioned by Paul Kelly.

The inappropriate claims occur in both Xu, Hansen et al. paper and Kehrwald, Thompson et al. paper in the parts of introduction or discussion (titled “implication” in Kehrwald et al.) parts. I think that these parts are not always critically reviewed in the peer review process. It seems that the authors are not experts of water resources. (I thought Yao should be one but now I doubt it.) Certainly the big names (Hansen and Thompson) are not. I guess that the hard core parts of the papers (soot in Xu et al. and isotopes in ice samples in Kehrwald et al.) are good studies and that these parts got appropriate peer review. (Rather, peer reviewers are usually chosen to evaluate the hard core parts.)

I discussed this issue somewhat longer in the blog Klimazwiebel of von Storch et al. (again) as comments to the article on “Over the top?” (by Reiner Grundmann on 31 Jan. 2010).